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1.
J Biomed Inform ; 151: 104620, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38462064

RESUMO

OBJECTIVE: Large language models (LLMs) such as ChatGPT are increasingly explored in medical domains. However, the absence of standard guidelines for performance evaluation has led to methodological inconsistencies. This study aims to summarize the available evidence on evaluating ChatGPT's performance in answering medical questions and provide direction for future research. METHODS: An extensive literature search was conducted on June 15, 2023, across ten medical databases. The keyword used was "ChatGPT," without restrictions on publication type, language, or date. Studies evaluating ChatGPT's performance in answering medical questions were included. Exclusions comprised review articles, comments, patents, non-medical evaluations of ChatGPT, and preprint studies. Data was extracted on general study characteristics, question sources, conversation processes, assessment metrics, and performance of ChatGPT. An evaluation framework for LLM in medical inquiries was proposed by integrating insights from selected literature. This study is registered with PROSPERO, CRD42023456327. RESULTS: A total of 3520 articles were identified, of which 60 were reviewed and summarized in this paper and 17 were included in the meta-analysis. ChatGPT displayed an overall integrated accuracy of 56 % (95 % CI: 51 %-60 %, I2 = 87 %) in addressing medical queries. However, the studies varied in question resource, question-asking process, and evaluation metrics. As per our proposed evaluation framework, many studies failed to report methodological details, such as the date of inquiry, version of ChatGPT, and inter-rater consistency. CONCLUSION: This review reveals ChatGPT's potential in addressing medical inquiries, but the heterogeneity of the study design and insufficient reporting might affect the results' reliability. Our proposed evaluation framework provides insights for the future study design and transparent reporting of LLM in responding to medical questions.


Assuntos
Inteligência Artificial , Comunicação , Bases de Dados Factuais , Reprodutibilidade dos Testes
2.
Br J Haematol ; 204(5): 2057-2065, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38302093

RESUMO

Increased iron loss may reduce the effectiveness of iron supplementation. The objective of this study was to determine if daily oral iron supplementation increases iron loss, measured using a stable isotope of iron (58Fe). We enrolled and dewormed 24 iron-depleted Kenyan children, 24-27 months of age, whose body iron was enriched and equilibrated with 58Fe given at least 1 year earlier. Over 3 months of supplementation (6 mg iron/kg body weight [BW]/day), mean (±SD) iron absorption was 1.10 (±0.28) mg/day. During supplementation, 0.55 (±0.36) mg iron/day was lost, equal to half of the amount of absorbed iron. Supplementation did not increase faecal haem/porphyrin or biomarkers of enterocyte damage and gut or systemic inflammation. Using individual patient data, we examined iron dose, absorption and loss among all available long-term iron isotopic studies of supplementation. Expressed in terms of body weight, daily iron loss was correlated significantly with iron absorption (Pearson's r = 0.66 [95% confidence interval 0.48-0.78]) but not with iron dose (r = 0.16 [95% CI -0.10-0.40]). The results of this study indicate that iron loss is increased with daily oral iron supplementation and may blunt the efficacy of iron supplements in children. This study was registered at ClinicalTrials.gov as NCT04721964.


Assuntos
Suplementos Nutricionais , Isótopos de Ferro , Ferro , Humanos , Feminino , Masculino , Pré-Escolar , Quênia , Ferro/metabolismo , Ferro/administração & dosagem , Anemia Ferropriva/tratamento farmacológico , Lactente
3.
Pediatr Blood Cancer ; 71(4): e30883, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38279826

RESUMO

BACKGROUND: Chemotherapy-induced nausea and vomiting (CINV) is common in children undergoing cancer treatment, and significantly impacts quality of life. Clinical practice guidelines (CPGs) have been developed to guide CINV management, though many patients do not receive guideline-concordant care. Few studies have examined provider perspectives on CINV management or preferred improvement approaches, or pediatric patient perception of CINV control. METHODS: A cross-sectional study of pediatric oncology providers was conducted at a large freestanding children's hospital. Providers completed an anonymous online survey about CINV control in patients admitted for scheduled chemotherapy, and their knowledge and utilization of CINV CPGs. A survey of English and Spanish-speaking pediatric oncology patients admitted for scheduled chemotherapy was conducted to assess CINV management, with key demographics used to understand association with perceptions and adherence to antiemetic guidelines. RESULTS: For providers, 75% of respondents felt CINV management could be moderately or extremely improved, significantly more so by chemotherapy prescribers and pediatric medical residents than nurses. Over half of respondents did not have awareness of CINV CPGs, particularly pediatric medical residents. For patients, nausea was reported to be extremely well controlled in 44% of cases, and vomiting extremely well controlled in 50% of cases. There were no significant differences in patient-reported CINV across demographics, when considering emetogenicity of chemotherapy received, or concordance to guidelines. CONCLUSIONS: Implementing education in this area may help to improve provider comfort, and ultimately, the patient experience. Future studies will expand upon this novel patient perception, and develop and evaluate CINV management interventions.


Assuntos
Antieméticos , Antineoplásicos , Neoplasias , Humanos , Criança , Qualidade de Vida , Estudos Transversais , Neoplasias/tratamento farmacológico , Náusea/induzido quimicamente , Náusea/prevenção & controle , Vômito/induzido quimicamente , Vômito/prevenção & controle , Antineoplásicos/efeitos adversos , Centros Médicos Acadêmicos
4.
Stroke ; 55(1): 69-77, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38063018

RESUMO

BACKGROUND: Aortic arch plaques are associated with an increased risk of ischemic stroke in patients with cryptogenic stroke or prior embolic events. However, this relationship is unclear in the community. We investigated (1) the long-term risk of stroke and cardiovascular events associated with arch plaques and (2) whether statin therapy prescribed for any indication modified the association. METHODS: A total of 934 stroke-free participants (72±9 years; 37% men) from the CABL study (Cardiovascular Abnormalities and Brain Lesion) were evaluated. Arch plaques were assessed by suprasternal transthoracic echocardiography; plaques ≥4 mm in thickness were classified as large plaques. The primary outcome was ischemic stroke; the secondary outcome was combined cardiovascular events (ischemic stroke, myocardial infarction, and cardiovascular death). The plaque-related risk of outcomes was also analyzed according to the presence of statin treatment. No plaque was used as a reference. RESULTS: Aortic arch plaques were present in 645 participants (69.1%), with large plaques in 114 (12.2%). During a mean follow-up of 11.3±3.6 years, 236 (25.3%) cardiovascular events occurred (76 ischemic strokes, 27 myocardial infarctions, and 133 cardiovascular deaths). Large arch plaques were independently associated with combined events (adjusted hazard ratio, 2.19 [95% CI, 1.40-3.43]) but not stroke alone (adjusted hazard ratio, 1.09 [95% CI, 0.50-2.38]). The association between large plaques and cardiovascular events was significant in participants receiving statins (adjusted hazard ratio, 2.57 [95% CI, 1.52-4.37]) but not in others; however, participants on statin treatment also had a worse risk profile (higher body mass index, greater frequencies of hypertension, diabetes, and coronary artery disease). CONCLUSIONS: Aortic arch plaques may be a marker of cardiovascular risk rather than a direct embolic stroke source in older adults without prior stroke. The efficacy of broader cardiovascular risk factors control, beyond cholesterol levels alone, for primary prevention of cardiovascular events in individuals with aortic arch plaques may require further investigation.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , AVC Isquêmico , Infarto do Miocárdio , Placa Aterosclerótica , Acidente Vascular Cerebral , Masculino , Humanos , Idoso , Feminino , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Aorta Torácica/diagnóstico por imagem , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/etiologia , Placa Aterosclerótica/complicações , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/tratamento farmacológico , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/complicações , AVC Isquêmico/complicações
5.
Curr Alzheimer Res ; 20(6): 409-419, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37694796

RESUMO

BACKGROUND AND OBJECTIVES: Neuropsychiatric symptoms (NPS), including psychotic symptoms (hallucinations, illusions, delusions), agitation/aggression, and depressed mood, are common in individuals with Alzheimer's disease (AD) and predict poorer outcomes, including faster disease progression. We aimed to evaluate associations between NPS and cognition and dependence in a multi-ethnic sample of community-dwelling older adults with AD. METHODS: Predictors 3 (P3) is a cohort study of AD disease courses recruiting older adults aged 65 and above residing in upper Manhattan. A total of 138 of 293 participants had probable AD at the study baseline. We fit linear mixed models to examine longitudinal associations of time-varying NPS (psychotic symptoms, agitation/aggression, and depressed mood) with dependence and cognition, adjusted for race-ethnicity, sex, education, age, clinical dementia rating score, APOE-ε4, and comorbidity burden; separate interaction models were fit for age, Hispanic ethnicity, and sex. RESULTS: Psychotic symptoms were associated with faster rates of increasing dependence and declining cognition over time, agitation/aggression with faster rates of declining cognition, and depressed mood with faster rates of increasing dependence. Among psychotic symptoms, delusions, but not hallucinations or illusions, were associated with worse outcome trajectories. Depressed mood predicted an accelerated increase in dependence in males but not females. CONCLUSION: Our results confirm and extend prior results in clinic-based samples. The presence of NPS was associated with worse trajectories of dependence and cognition in this muti-ethnic sample of older adults with AD. Importantly, sex modified the association between depressed mood and dependence. Our results on NPS as predictors of differential AD progression in a community-dwelling, ethnically diverse sample serve to better inform the clinical care of patients and the future development of AD therapies.


Assuntos
Doença de Alzheimer , Ilusões , Masculino , Humanos , Idoso , Delusões/epidemiologia , Vida Independente , Estudos de Coortes , Doença de Alzheimer/diagnóstico , Alucinações , Cognição
6.
Am J Cardiol ; 206: 161-167, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37708746

RESUMO

Atrial fibrillation (AF) is frequent in older adults and associated with left atrial (LA) dysfunction. LA strain (LAε) and LA strain rate (LASR) may detect subclinical LA disease. We investigated whether reduced LAε and LASR predict new-onset AF in older adults without history of AF or stroke. LAε and LASR were assessed by speckle-tracking echocardiography in 824 participants from the community-based Cardiovascular Abnormalities and Brain Lesions study. Positive longitudinal LAε and LASR during ventricular systole, LASR during early ventricular diastole, and LASR during LA contraction were measured. Cause-specific hazards regression model evaluated the association of LAε and LASR with incident AF, adjusting for pertinent covariates. The mean age was 71.1 ± 9.2 years (313 men, 511 women). During a mean follow-up of 10.9 years, new-onset AF occurred in 105 participants (12.7%). Lower LAε and LASR at baseline were observed in patients with new-onset AF (all p <0.01). In multivariable analysis, positive longitudinal LAε (adjusted hazard ratio [HR] per SD decrease 2.05, confidence interval [CI] 1.24 to 3.36) and LASR during LA contraction (HR per SD increase 2.24, CI 1.37 to 3.65) remained associated with new-onset AF, independently of LA volumes and left ventricular function. Along with positive longitudinal LAε, reduced LASR during ventricular systole predicted AF in participants with LA volume below the median value (HR 2.54, CI 1.10 to 6.09), whereas reduced LASR during LA contraction predicted AF in participants with larger LA (HR 2.35, CI 1.31 to 4.23). In conclusion, reduced positive longitudinal LAε and LASR predict new-onset AF in older adults regardless of LA size and may improve AF risk stratification.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Masculino , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/epidemiologia , Átrios do Coração/diagnóstico por imagem , Ecocardiografia , Função Ventricular Esquerda
7.
J Pediatr ; 263: 113721, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37673205

RESUMO

OBJECTIVE: To evaluate the frequency of iron status assessment in pediatric heart failure and the prevalence and adverse effects of absolute iron deficiency in dilated cardiomyopathy-induced heart failure. STUDY DESIGN: We retrospectively reviewed records of children with chronic heart failure at our center between 2010 and 2020. In children with dilated cardiomyopathy, we analyzed baseline cardiac function, hemoglobin level, and subsequent risk of composite adverse events (CAE), including death, heart transplant, ventricular assist device (VAD) placement, and transplant registry listing. Absolute iron deficiency and iron sufficiency were defined as transferrin saturations <20% and ≥30%, respectively; and indeterminant iron status as 20%-29%. RESULTS: Of 799 patients with chronic heart failure, 471 (59%) had no iron-related laboratory measurements. Of 68 children with dilated cardiomyopathy, baseline transferrin saturation, and quantitative left ventricular ejection fraction (LVEF), 33 (49%) and 14 (21%) were iron deficient and sufficient, respectively, and 21 (31%) indeterminant. LVEF was reduced to 23.6 ± 12.1% from 32.9 ± 16.8% in iron deficiency and sufficiency, respectively (P = .04), without a significant difference in hemoglobin. After stratification by New York Heart Association classification, in advanced class IV, hemoglobin was reduced to 10.9 ± 1.3 g/dL vs 12.7 ± 2.0 g/dL in iron deficiency and sufficiency, respectively (P = .01), without a significant difference in LVEF. CONCLUSIONS: In this single-center study, iron deficiency was not monitored in most children with chronic heart failure. In pediatric dilated cardiomyopathy-induced heart failure, absolute iron deficiency was prevalent and associated with clinically consequential and possibly correctable decreases in cardiac function and hemoglobin concentration.


Assuntos
Cardiomiopatia Dilatada , Insuficiência Cardíaca , Deficiências de Ferro , Humanos , Criança , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Dilatada/terapia , Volume Sistólico , Estudos Retrospectivos , Função Ventricular Esquerda , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/terapia , Ferro/farmacologia , Doença Crônica , Hemoglobinas , Transferrinas/farmacologia
8.
J Am Heart Assoc ; 12(16): e030274, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37577940

RESUMO

Background Premature ventricular contractions (PVCs) and nonsustained ventricular tachycardia (NSVT) are known to be associated with reduced left ventricular (LV) ejection fraction and adverse outcomes in patients with structural heart disease. The relationship between subclinical LV dysfunction and ventricular arrhythmias in the general population is not established. Methods and Results Participants in the SAFARIS (Subclinical Atrial Fibrillation and Risk of Ischemic Stroke) study with normal left ventricular ejection fraction (n=503; mean age 77 years, 63% women) underwent 14-day electrocardiographic monitoring and 2-dimensional echocardiography. Frequent PVCs were defined as PVCs >500 per 24 hours and NSVT as ≥4 consecutive ventricular ectopic beats. Reduced LV global longitudinal strain (GLS) was used as an indicator of subclinical LV dysfunction. Seventy-six participants (15.1%) had PVCs >500/d, 117 (23.3%) had NSVT episodes. LV GLS was significantly reduced in both frequent PVCs and NSVT groups (P<0.01). In multivariable analyses, lower LV GLS was associated with frequent PVCs (adjusted odds ratio [aOR], 1.19 [95% CI, 1.09-1.30 per unit reduction]; P<0.001) and NSVT (aOR, 1.09 [95% CI, 1.01-1.17]; P=0.036) independently of established risk factors and other echocardiographic parameters. Abnormal LV GLS (>-15.8%) carried a 2-fold increase in risk of ventricular arrhythmias (aOR, 2.18, P=0.029 for PVCs; aOR, 2.09, P=0.026 for NSVT). Conclusions PVCs and NSVT episodes were frequent in this community-based elderly cohort with normal left ventricular ejection fraction and were independently associated with lower LV GLS. The association between LV dysfunction and ventricular arrhythmias is present at an early, subclinical stage, an observation that carries possible preventative implications.


Assuntos
Taquicardia Ventricular , Disfunção Ventricular Esquerda , Complexos Ventriculares Prematuros , Humanos , Feminino , Idoso , Masculino , Volume Sistólico , Função Ventricular Esquerda , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/epidemiologia , Ecocardiografia/métodos , Complexos Ventriculares Prematuros/complicações , Complexos Ventriculares Prematuros/diagnóstico , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/complicações
9.
Front Neuroimaging ; 2: 1072759, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37554641

RESUMO

Magnetic Resonance Imaging (MR Imaging) is routinely employed in diagnosing Alzheimer's Disease (AD), which accounts for up to 60-80% of dementia cases. However, it is time-consuming, and protocol optimization to accelerate MR Imaging requires local expertise since each pulse sequence involves multiple configurable parameters that need optimization for contrast, acquisition time, and signal-to-noise ratio (SNR). The lack of this expertise contributes to the highly inefficient utilization of MRI services diminishing their clinical value. In this work, we extend our previous effort and demonstrate accelerated MRI via intelligent protocolling of the modified brain screen protocol, referred to as the Gold Standard (GS) protocol. We leverage deep learning-based contrast-specific image-denoising to improve the image quality of data acquired using the accelerated protocol. Since the SNR of MR acquisitions depends on the volume of the object being imaged, we demonstrate subject-specific (SS) image-denoising. The accelerated protocol resulted in a 1.94 × gain in imaging throughput. This translated to a 72.51% increase in MR Value-defined in this work as the ratio of the sum of median object-masked local SNR values across all contrasts to the protocol's acquisition duration. We also computed PSNR, local SNR, MS-SSIM, and variance of the Laplacian values for image quality evaluation on 25 retrospective datasets. The minimum/maximum PSNR gains (measured in dB) were 1.18/11.68 and 1.04/13.15, from the baseline and SS image-denoising models, respectively. MS-SSIM gains were: 0.003/0.065 and 0.01/0.066; variance of the Laplacian (lower is better): 0.104/-0.135 and 0.13/-0.143. The GS protocol constitutes 44.44% of the comprehensive AD imaging protocol defined by the European Prevention of Alzheimer's Disease project. Therefore, we also demonstrate the potential for AD-imaging via automated volumetry of relevant brain anatomies. We performed statistical analysis on these volumetric measurements of the hippocampus and amygdala from the GS and accelerated protocols, and found that 27 locations were in excellent agreement. In conclusion, accelerated brain imaging with the potential for AD imaging was demonstrated, and image quality was recovered post-acquisition using DL-based image denoising models.

10.
Clin Imaging ; 102: 53-59, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37549563

RESUMO

PURPOSE: Brain and spinal cord tumors are the second most common cancer in children and account for one out of four cancers diagnosed. However, the long acquisition times associated with acquiring both data types prohibit using quantitative MR (qMR) in pediatric imaging protocols. This study aims to demonstrate the tailored magnetic resonance fingerprinting's (TMRF) ability to simultaneously provide quantitative maps (T1, T2) and multi-contrast qualitative images (T1 weighted, T1 FLAIR, T2 weighted) rapidly in pediatric brain tumor patients. METHODS: In this work, we imaged five pediatric patients with brain tumors (resected/residual) using TMRF at 3 T. We compared the TMRF-derived T2 weighted images with those from the vendor-supplied sequence (as the gold standard, GS) for healthy and pathological tissue signal intensities. The relaxometric maps from TMRF were subjected to a region of interest (ROI) analysis to differentiate between healthy and pathological tissues. We performed the Wilcoxon rank sum test to check for significant differences between the two tissue types. RESULTS: We found significant differences (p < 0.05) in both T1 and T2 ROI values between the two tissue types. A strong correlation was found between the TMRF-based T2 weighted and GS signal intensities for the healthy (correlation coefficient, r = 0.99) and pathological tissues (r = 0.88). CONCLUSION: The TMRF implementation provides the two relaxometric maps and can potentially save ~2 min if it replaces the T2-weighted imaging in the current protocol.


Assuntos
Neoplasias Encefálicas , Imageamento por Ressonância Magnética , Humanos , Criança , Imageamento por Ressonância Magnética/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Espectroscopia de Ressonância Magnética , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Estatísticas não Paramétricas
11.
Phys Med Biol ; 68(17)2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37489867

RESUMO

The purpose of this study is to demonstrate the first work ofT1-based magnetic resonance thermometry using magnetic resonance fingerprinting (dubbed MRFT). We compared temperature estimation of MRFT with proton resonance frequency shift (PRFS) thermometry onex vivobovine muscle. We demonstrated MRFT's feasibility in predicting temperature onex vivobovine muscles with deep brain stimulation (DBS) lead.B0maps generated from MRFT were compared with gold standardB0maps near the DBS lead. MRFT and PRFS estimated temperatures were compared in the presence of motion. All experiments were performed on a 3 Tesla whole-body GE Premier system with a 21-channel receive head coil (GE Healthcare, Milwaukee, WI). Four fluoroptic probes were used to measure the temperature at the center of a cold muscle (probe 1), the room temperature water bottle (probe 2), and the center and periphery of the heated muscle (probes 3 and 4). We selected regions of interest (ROIs) around the location of the probes and used simple linear regression to generate the temperature sensitivity calibration equations that convertT1maps and Δsmaps to temperature maps. We then repeated the same setup and compared MRFT and PRFS thermometry temperature estimation with gold standard probe measurements. For the MRFT experiment on DBS lead, we taped the probe to the tip of the DBS lead and used a turbo spin echo sequence to induce heating near the lead. We selected ROIs around the tip of the lead to compare MRFT temperature estimation with probe measurements and compared with PRFS temperature estimation. Vendor-suppliedB0mapping sequence was acquired to compare with MRFT-generatedB0maps. We found strong linear relationships (R2> 0.958) betweenT1and temperature and Δsand temperatures in our temperature sensitivity calibration experiment. MRFT and PRFS thermometry both accurately predict temperature (RMSE < 1.55 °C) compared to probe measurements. MRFT estimated temperature near DBS lead has a similar trend as the probe temperature. BothB0maps show inhomogeneities around the lead. MRFT estimated temperature is less sensitive to motion.


Assuntos
Chumbo , Termometria , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Termometria/métodos , Temperatura , Imagens de Fantasmas
12.
J Alzheimers Dis ; 95(1): 93-117, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37482990

RESUMO

BACKGROUND: The major aims of the three Predictors Studies have been to further our understanding of Alzheimer's disease (AD) progression sufficiently to predict the length of time from disease onset to major disease outcomes in individual patients with AD. OBJECTIVES: To validate a longitudinal Grade of Membership (L-GoM) prediction algorithm developed using clinic-based, mainly white patients from the Predictors 2 Study in a statistically representative community-based sample of Hispanic (N = 211) and non-Hispanic (N = 62) older adults (with 60 males and 213 females) from the Predictors 3 Study and extend the algorithm to mild cognitive impairment (MCI). METHODS: The L-GoM model was applied to data collected at the initial Predictors 3 visit for 150 subjects with AD and 123 with MCI. Participants were followed annually for up to seven years. Observed rates of survival and need for full-time care (FTC) were compared to those predicted by the algorithm. RESULTS: Initial MCI/AD severity in Predictors 3 was substantially higher than among clinic-based AD patients enrolled at the specialized Alzheimer's centers in Predictors 2. The observed survival and need for FTC followed the L-GoM model trajectories in individuals with MCI or AD, except for N = 32 subjects who were initially diagnosed with AD but reverted to a non-AD diagnosis on follow-up. CONCLUSION: These findings indicate that the L-GoM model is applicable to community-dwelling, multiethnic older adults with AD. They extend the use of the model to the prediction of outcomes for MCI. They also justify release of our L-GoM calculator at this time.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Masculino , Feminino , Humanos , Idoso , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/psicologia , Vida Independente , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Progressão da Doença
13.
J Appl Stat ; 50(9): 1980-1991, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37378272

RESUMO

To study the effect of exposure mixture on the continuous health outcomes, one can use the linear model with a weighted sum of multiple standardized exposure variables as an index predictor and its coefficient for the overall effect. The unknown weights typically range between zero and one, indicating contributions of individual exposures to the overall effect. Because the weight parameters present only when the parameter for overall effect is non-zero, testing hypotheses on the overall effect can be challenging, especially when the number of exposure variables is above two. This paper presents a working model based approach to estimate the parameter for overall effect and to test specific hypotheses, including two tests for detecting the overall effect and one test for detecting unequal weights when the overall effect is evident. The statistics are computationally easy and one can apply existing statistical software to perform the analysis. A simulation study shows that the proposed estimators for the parameters of interest may have better finite sample performance than some other estimators.

14.
Atheroscler Plus ; 52: 18-22, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37250431

RESUMO

Background and aims: The presence of aortic arch plaques (AAP) is significantly associated with increased cardiovascular morbidity and mortality. Few studies have examined the incidence of AAP progression and factors which may contribute to it using transthoracic echocardiography (TTE). The objective of this study was to utilize sequential imaging of the aortic arch using TTE to examine the rate of AAP progression and its risk factors in a cohort of older adults. Methods: Participants enrolled in both the Cardiovascular Abnormalities and Brain Lesion study (years 2005-2010) and the Subclinical Atrial Fibrillation and Risk of Ischemic Stroke study (2014-2019) who underwent TTE with assessment of aortic arch plaques at both time points represent the study cohort. Results: 300 participants were included in the study. Mean age was 67.8 ± 7.5 years at baseline, and 76.7 ± 6.8 years at follow-up; 197 (65.7%) were women. At baseline, 87 (29%) had no significant AAP, 182 (60.7%) had evidence of small AAP (2.0-3.9 mm) and 31 (10.3%) had evidence of large (≥4 mm) AAP. At the time of follow-up assessment, 157 (52.3%) of participants exhibited progression of AAP with 70 (23.3%) having mild progression and 87 (29%) having severe progression. There were no significant demographic or clinical predictors of AAP progression except baseline plaque thickness itself which was significantly lower in the group with AAP progression. Conclusions: Our study demonstrates a high prevalence of AAP on TTE exam in a population-based cohort of older adults with a high incidence of AAP progression. TTE is a useful test for baseline and follow up imaging of AAP, even in subjects with no or little AAP at baseline.

15.
Int J Cardiol ; 381: 76-80, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37030403

RESUMO

BACKGROUND: Aortic valve calcification (AVC) is a common valvular abnormality that predisposes to stenosis; AVC progression and factors associated with it remain unclear. We investigated the association of clinical factors and serum biomarkers with AVC progression in a population-based cohort of older adults. METHODS: Participants enrolled in both the Cardiovascular Abnormalities and Brain Lesion study (CABL; years 2005-2010) and the Subclinical Atrial Fibrillation And Risk of Ischemic Stroke study (SAFARIS;2014-2019) represent the study cohort. AVC was defined as bright dense echoes >1 mm in size on ≥1 cusps; each cusp was graded on a scale of 0 (normal) to 3 (severe calcification) at baseline and follow up. Serum biomarkers were measured at the time of follow-up assessment. RESULTS: 373 participants (mean 68.1 ± 7.6 years of age, 146 M/ 227F) were included. 139 (37%) had AVC progression;93 (25%) had mild progression (1 grade), and 46 (12%) had moderate-severe progression (≥2 grades). The only significant clinical predictor of any progression was the use of anti-hypertensive medication which was associated with older age, higher BMI and more frequent hypertension, diabetes and hyperlipidemia. In multivariable analysis including biomarkers, transforming growth factor beta 1 (TGF-ß1) was significantly associated with both all and moderate-severe AVC progression. CONCLUSIONS: A significant number of elderly subjects with AVC show progression of their valve disease; individual vascular risk factors are not associated with AVC progression, although a combined effect may exist. Higher levels of TGF-ß1 are observed in individuals with AVC progression.


Assuntos
Estenose da Valva Aórtica , Valva Aórtica , Humanos , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/patologia , Fator de Crescimento Transformador beta1 , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/epidemiologia , Biomarcadores
16.
PLoS One ; 18(3): e0283349, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36996064

RESUMO

BACKGROUND: Acute chest syndrome (ACS) is an acute complication in SCD but its effects on lung function are not well understood. Inflammation is a key component of SCD pathophysiology but with an unclear association with lung function. We hypothesized that children with ACS had worse lung function than children without ACS and aimed to investigate the association of lung function deficits with inflammatory cytokines. METHODS: Patients enrolled in a previous 2-year randomized clinical trial who had consented to future data use, were enrolled for the present exploratory study. Patients were categorized into ACS and non-ACS groups. Demographic and clinical information were collected. Serum samples were used for quantification of serum cytokines and leukotriene B4 levels and pulmonary function tests (PFTs) were assessed. RESULTS: Children with ACS had lower total lung capacity (TLC) at baseline and at 2 years, with a significant decline in forced expiratory volume in 1 sec (FEV1) and mid-maximal expiratory flow rate (FEF25-75%) in the 2 year period (p = 0.015 and p = 0.039 respectively). For children with ACS, serum cytokines IL-5, and IL-13 were higher at baseline and at 2 years compared to children with no ACS. IP-10 and IL-6 were negatively correlated with PFT markers. In multivariable regression using generalized estimating equation approach for factors predicting lung function, age was significantly associated FEV1 (p = 0.047) and ratio of FEV1 and forced vital capacity (FVC)- FEV1/FVC ratio (p = 0.006); males had lower FEV1/FVC (p = 0.035) and higher TLC (p = 0.031). Asthma status was associated with FEV1 (p = 0.017) and FVC (p = 0.022); history of ACS was significantly associated with TLC (p = 0.027). CONCLUSION: Pulmonary function abnormalities were more common and inflammatory markers were elevated in patients with ACS, compared with those without ACS. These findings suggest airway inflammation is present in children with SCD and ACS, which could be contributing to impaired pulmonary function.


Assuntos
Síndrome Torácica Aguda , Anemia Falciforme , Pneumopatias , Masculino , Criança , Humanos , Síndrome Torácica Aguda/complicações , Anemia Falciforme/complicações , Pulmão , Capacidade Vital , Pneumopatias/complicações , Volume Expiratório Forçado , Inflamação/complicações , Citocinas
17.
J Endocr Soc ; 7(5): bvad028, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36922916

RESUMO

Context: Acromegaly presents a unique pattern of lower adiposity and insulin resistance in active disease but reduction in insulin resistance despite a rise in adiposity after surgery. Depot-specific adipose tissue masses and ectopic lipid are important predictors of insulin resistance in other populations, but whether they are in acromegaly is unknown. Long-term persistence of body composition changes after surgery is unknown. Objective: To determine how depot-specific body composition and ectopic lipid relate to insulin resistance in active acromegaly and whether their changes with surgery are sustained long-term. Methods: Cross-sectional study in patients with active acromegaly and longitudinal study in newly diagnosed patients studied before and in long-term follow-up, 3 (1-8) years (median, range), after surgery. Seventy-one patients with active acromegaly studied cross-sectionally and 28 with newly diagnosed acromegaly studied longitudinally. Main outcome measures were visceral (VAT), subcutaneous (SAT), and intermuscular adipose tissue masses by whole-body magnetic resonance imaging; intrahepatic lipid (IHL) by proton magnetic resonance spectroscopy; insulin resistance measures derived from fasting; and oral glucose tolerance test insulin and glucose levels. Results: SAT and insulin-like growth factor 1 level, but not VAT or IHL, were independent predictors of insulin resistance in active acromegaly. VAT, SAT, and IHL gains were sustained long-term after surgery. VAT mass rise with surgery correlated inversely with rise in QUICKI while SAT rise correlated with fall in the Homeostatic Model Assessment score. Conclusion: SAT and disease activity are important predictors of insulin resistance in active acromegaly. Adiposity gains are sustained long-term after surgical treatment and impact on the accompanying improvement in insulin resistance.

18.
JAMA Cardiol ; 8(4): 317-325, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36753086

RESUMO

Importance: The risk of ischemic stroke is higher among patients with left atrial (LA) enlargement. Left atrial strain (LAε) and LA strain rate (LASR) may indicate LA dysfunction when LA volumes are still normal. The association of LAε with incident ischemic stroke in the general population is not well established. Objective: To investigate whether LAε and LASR are associated with new-onset ischemic stroke among older adults. Design: The Cardiovascular Abnormalities and Brain Lesions study was conducted from September 29, 2005, to July 6, 2010, to investigate cardiovascular factors associated with subclinical cerebrovascular disease. A total of 806 participants in the Northern Manhattan Study who were aged 55 years or older without history of prior stroke or atrial fibrillation (AF) were included, and annual follow-up telephone interviews were completed May 22, 2022. Statistical analysis was performed from June through November 2022. Exposures: Left atrial strain and LASR were assessed by speckle-tracking echocardiography. Global peak positive longitudinal LAε and positive longitudinal LASR during ventricular systole, global peak negative longitudinal LASR during early ventricular diastole, and global peak negative longitudinal LASR during LA contraction were measured. Brain magnetic resonance imaging was used to detect silent brain infarcts and white matter hyperintensities at baseline. Main Outcomes and Measures: Risk analysis with cause-specific Cox proportional hazards regression modeling was used to assess the association of positive longitudinal LAε and positive longitudinal LASR with incident ischemic stroke, adjusting for other stroke risk factors, including incident AF. Results: The study included 806 participants (501 women [62.2%]) with a mean (SD) age of 71.0 (9.2) years; 119 participants (14.8%) were Black, 567 (70.3%) were Hispanic, and 105 (13.0%) were White. During a mean (SD) follow-up of 10.9 (3.7) years, new-onset ischemic stroke occurred in 53 participants (6.6%); incident AF was observed in 103 participants (12.8%). Compared with individuals who did not develop ischemic stroke, participants with ischemic stroke had lower positive longitudinal LAε and negative longitudinal LASR at baseline. In multivariable analysis, the lowest (ie, closest to zero) vs all other quintiles of positive longitudinal LAε (adjusted hazard ratio [HR], 3.12; 95% CI, 1.56-6.24) and negative longitudinal LASR during LA contraction (HR, 2.89; 95% CI, 1.44-5.80) were associated with incident ischemic stroke, independent of left ventricular global longitudinal strain and incident AF. Among participants with a normal LA size, the lowest vs all other quintiles of positive longitudinal LAε (HR, 4.64; 95% CI, 1.55-13.89) and negative longitudinal LASR during LA contraction (HR, 11.02; 95% CI 3.51-34.62) remained independently associated with incident ischemic stroke. Conclusions and Relevance: This cohort study suggests that reduced positive longitudinal LAε and negative longitudinal LASR are independently associated with ischemic stroke in older adults. Assessment of LAε and LASR by speckle-tracking echocardiography may improve stroke risk stratification in elderly individuals.


Assuntos
Fibrilação Atrial , AVC Isquêmico , Acidente Vascular Cerebral , Idoso , Humanos , Feminino , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , Estudos de Coortes , Átrios do Coração/diagnóstico por imagem
19.
Eur Heart J Cardiovasc Imaging ; 24(4): 522-531, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35900282

RESUMO

AIMS: Heart disease is associated with an increased risk for ischaemic stroke. However, the predictive value of reduced left ventricular ejection fraction (LVEF) for stroke is controversial and only observed in patients with severe reduction. LV global longitudinal strain (LV GLS) can detect subclinical LV systolic impairment when LVEF is normal. We investigated the prognostic role of LV GLS for incident stroke in a predominantly elderly cohort. METHODS AND RESULTS: Two-dimensional echocardiography with speckle tracking was performed in the Cardiac Abnormalities and Brain Lesions (CABL) study. Among 708 stroke-free participants (mean age 71.4 ± 9.4 years, 60.9% women), abnormal LV GLS (>-14.7%: 95% percentile of the subgroup without risk factors) was detected in 133 (18.8%). During a mean follow-up of 10.8 ± 3.9 years, 47 participants (6.6%) experienced an ischaemic stroke (26 cardioembolic or cryptogenic, 21 other subtypes). The cumulative incidence of ischaemic stroke was significantly higher in participants with abnormal LV GLS than with normal LV GLS (P < 0.001). In multivariate stepwise logistic regression analysis, abnormal LV GLS was associated with ischaemic stroke independently of cardiovascular risk factors including LVEF, LV mass, left atrial volume, subclinical cerebrovascular disease at baseline, and incident atrial fibrillation [hazard ratio (HR): 2.69, 95% confidence interval (CI): 1.47-4.92; P = 0.001]. Abnormal LV GLS independently predicted cardioembolic or cryptogenic stroke (adjusted HR: 3.57, 95% CI: 1.51-8.43; P = 0.004) but not other subtypes. CONCLUSION: LV GLS was a strong independent predictor of ischaemic stroke in a predominantly elderly stroke-free cohort. Our findings provide insights into the brain-heart interaction and may help improve stroke primary prevention strategies.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Disfunção Ventricular Esquerda , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Encéfalo/diagnóstico por imagem , Anormalidades Cardiovasculares , AVC Isquêmico , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/epidemiologia , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/epidemiologia , Função Ventricular Esquerda
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